VJ> There is no problem accessing disk1..n via the FLT (using IOCtl), but
 VJ> I don't want to display RAID0 as a possible part of a new array as I
 VJ> already displayed it via information from FLT IOCtl and writing
 VJ> configuration data to it would be ignored anyway (sector 0 as OS/2
 VJ> knows it isn't the real first sector).

I'd say that this is a problem in your setup program, not your FLT or
OS2DASD.DMD.  Your setup program needs to enumerate all of the physical
discs, and remember both which ones it has determined are software RAID
arrays (by doing a presence check of some sort for your FLT via a
DosDevIOCtl), and which ones it has determined are not.  The setup program
should then only present the physical discs in the second list when the
user chooses to create a new RAID array.

 ¯ JdeBP ®

--- FleetStreet 1.19 NR